7-Segment Display Interface with 8051 Microcontrollers

Seven-segment displays are nothing more than well arranged LEDs inside a box — actually eight of them when you count the decimal point. As such, the interfacing code should be as simple as interfacing a row of LEDs. Indeed it is simple, though the complexity is in multiplexing displays.

Here, we'll write a program that will display the number 4321 on the seven-segment LED displays of the PCAM+ board.

First, make these connections using the jumper wires, but be sure to use the D1 etc. pins on the side of the seven-segment LEDs and not the ones with the same names used previously for the single-row LED examples.

Connect P2.0 from the microcontroller to pin D1 of the seven-segment LEDs

Connect P2.1 from the microcontroller to pin D2 of the seven-segment LEDs

Connect P2.2 from the microcontroller to pin D3 of the seven-segment LEDs

Connect P2.3 from the microcontroller to pin D4 of the seven-segment LEDs

Likewise, connect P3.0 through P3.7 to pins "a" through "•" on the other side of the seven-segment LEDs